Satellite antennas, in particular parabolic antennas popularly referred to as “satellite dishes” have come into widespread use with the advent of satellite-based television. Such satellite dishes are known to require careful alignment in order to achieve a good reception performance. In order to allow for elevation and azimuth alignment of such antennas, in particular of antennas for private household use, simple antenna holders have been designed in which e.g. a ball-and-socket joint ensured to degrees of rotational freedom. In an unlocked state of this joint, the dish was pivoted freehandedly until an appropriate alignment was found, and then the joint was locked in order to fix the dish in this alignment.
Forthcoming applications such as interactive television, high speed internet access by satellite etc. will require small and economic satellite antenna designs which enable a user not only to receive a downlink signal from the satellite, but also to transmit data in the uplink direction, towards the satellite.
For uplink transmission, the alignment of the satellite antenna with respect to the satellite is much more critical than for downlink. This is because the receiving characteristic of the satellite dish on earth, being very narrow and aimed at the satellite, receives very little noise besides the signal from the satellite, whereas a satellite antenna that must be able to receive uplink signals from numerous satellite dishes at various places on earth is exposed to a much higher level of noise. Therefore, it is expected that for bi-directional applications, earthborn satellite antennas will have to be aligned with an accuracy of approximately 0.1 degrees. This is a level of precision which is not reliably achieved with the conventional satellite dish holders described above.